1 /* $NetBSD: kern_exec.c,v 1.414 2015/09/11 01:23:37 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /*- 30 * Copyright (C) 1993, 1994, 1996 Christopher G. Demetriou 31 * Copyright (C) 1992 Wolfgang Solfrank. 32 * Copyright (C) 1992 TooLs GmbH. 33 * All rights reserved. 34 * 35 * Redistribution and use in source and binary forms, with or without 36 * modification, are permitted provided that the following conditions 37 * are met: 38 * 1. Redistributions of source code must retain the above copyright 39 * notice, this list of conditions and the following disclaimer. 40 * 2. Redistributions in binary form must reproduce the above copyright 41 * notice, this list of conditions and the following disclaimer in the 42 * documentation and/or other materials provided with the distribution. 43 * 3. All advertising materials mentioning features or use of this software 44 * must display the following acknowledgement: 45 * This product includes software developed by TooLs GmbH. 46 * 4. The name of TooLs GmbH may not be used to endorse or promote products 47 * derived from this software without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 50 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 51 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 52 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 53 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 54 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 55 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 56 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 57 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 58 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 59 */ 60 61 #include <sys/cdefs.h> 62 __KERNEL_RCSID(0, "$NetBSD: kern_exec.c,v 1.414 2015/09/11 01:23:37 christos Exp $"); 63 64 #include "opt_exec.h" 65 #include "opt_execfmt.h" 66 #include "opt_ktrace.h" 67 #include "opt_modular.h" 68 #include "opt_syscall_debug.h" 69 #include "veriexec.h" 70 #include "opt_pax.h" 71 72 #include <sys/param.h> 73 #include <sys/systm.h> 74 #include <sys/filedesc.h> 75 #include <sys/kernel.h> 76 #include <sys/proc.h> 77 #include <sys/mount.h> 78 #include <sys/kmem.h> 79 #include <sys/namei.h> 80 #include <sys/vnode.h> 81 #include <sys/file.h> 82 #include <sys/filedesc.h> 83 #include <sys/acct.h> 84 #include <sys/atomic.h> 85 #include <sys/exec.h> 86 #include <sys/ktrace.h> 87 #include <sys/uidinfo.h> 88 #include <sys/wait.h> 89 #include <sys/mman.h> 90 #include <sys/ras.h> 91 #include <sys/signalvar.h> 92 #include <sys/stat.h> 93 #include <sys/syscall.h> 94 #include <sys/kauth.h> 95 #include <sys/lwpctl.h> 96 #include <sys/pax.h> 97 #include <sys/cpu.h> 98 #include <sys/module.h> 99 #include <sys/syscallvar.h> 100 #include <sys/syscallargs.h> 101 #if NVERIEXEC > 0 102 #include <sys/verified_exec.h> 103 #endif /* NVERIEXEC > 0 */ 104 #include <sys/sdt.h> 105 #include <sys/spawn.h> 106 #include <sys/prot.h> 107 #include <sys/cprng.h> 108 109 #include <uvm/uvm_extern.h> 110 111 #include <machine/reg.h> 112 113 #include <compat/common/compat_util.h> 114 115 #ifndef MD_TOPDOWN_INIT 116 #ifdef __USE_TOPDOWN_VM 117 #define MD_TOPDOWN_INIT(epp) (epp)->ep_flags |= EXEC_TOPDOWN_VM 118 #else 119 #define MD_TOPDOWN_INIT(epp) 120 #endif 121 #endif 122 123 struct execve_data; 124 125 static size_t calcargs(struct execve_data * restrict, const size_t); 126 static size_t calcstack(struct execve_data * restrict, const size_t); 127 static int copyoutargs(struct execve_data * restrict, struct lwp *, 128 char * const); 129 static int copyoutpsstrs(struct execve_data * restrict, struct proc *); 130 static int copyinargs(struct execve_data * restrict, char * const *, 131 char * const *, execve_fetch_element_t, char **); 132 static int copyinargstrs(struct execve_data * restrict, char * const *, 133 execve_fetch_element_t, char **, size_t *, void (*)(const void *, size_t)); 134 static int exec_sigcode_map(struct proc *, const struct emul *); 135 136 #ifdef DEBUG_EXEC 137 #define DPRINTF(a) printf a 138 #define COPYPRINTF(s, a, b) printf("%s, %d: copyout%s @%p %zu\n", __func__, \ 139 __LINE__, (s), (a), (b)) 140 static void dump_vmcmds(const struct exec_package * const, size_t, int); 141 #define DUMPVMCMDS(p, x, e) do { dump_vmcmds((p), (x), (e)); } while (0) 142 #else 143 #define DPRINTF(a) 144 #define COPYPRINTF(s, a, b) 145 #define DUMPVMCMDS(p, x, e) do {} while (0) 146 #endif /* DEBUG_EXEC */ 147 148 /* 149 * DTrace SDT provider definitions 150 */ 151 SDT_PROBE_DEFINE(proc,,,exec,exec, 152 "char *", NULL, 153 NULL, NULL, NULL, NULL, 154 NULL, NULL, NULL, NULL); 155 SDT_PROBE_DEFINE(proc,,,exec_success,exec-success, 156 "char *", NULL, 157 NULL, NULL, NULL, NULL, 158 NULL, NULL, NULL, NULL); 159 SDT_PROBE_DEFINE(proc,,,exec_failure,exec-failure, 160 "int", NULL, 161 NULL, NULL, NULL, NULL, 162 NULL, NULL, NULL, NULL); 163 164 /* 165 * Exec function switch: 166 * 167 * Note that each makecmds function is responsible for loading the 168 * exec package with the necessary functions for any exec-type-specific 169 * handling. 170 * 171 * Functions for specific exec types should be defined in their own 172 * header file. 173 */ 174 static const struct execsw **execsw = NULL; 175 static int nexecs; 176 177 u_int exec_maxhdrsz; /* must not be static - used by netbsd32 */ 178 179 /* list of dynamically loaded execsw entries */ 180 static LIST_HEAD(execlist_head, exec_entry) ex_head = 181 LIST_HEAD_INITIALIZER(ex_head); 182 struct exec_entry { 183 LIST_ENTRY(exec_entry) ex_list; 184 SLIST_ENTRY(exec_entry) ex_slist; 185 const struct execsw *ex_sw; 186 }; 187 188 #ifndef __HAVE_SYSCALL_INTERN 189 void syscall(void); 190 #endif 191 192 /* NetBSD emul struct */ 193 struct emul emul_netbsd = { 194 .e_name = "netbsd", 195 #ifdef EMUL_NATIVEROOT 196 .e_path = EMUL_NATIVEROOT, 197 #else 198 .e_path = NULL, 199 #endif 200 #ifndef __HAVE_MINIMAL_EMUL 201 .e_flags = EMUL_HAS_SYS___syscall, 202 .e_errno = NULL, 203 .e_nosys = SYS_syscall, 204 .e_nsysent = SYS_NSYSENT, 205 #endif 206 .e_sysent = sysent, 207 #ifdef SYSCALL_DEBUG 208 .e_syscallnames = syscallnames, 209 #else 210 .e_syscallnames = NULL, 211 #endif 212 .e_sendsig = sendsig, 213 .e_trapsignal = trapsignal, 214 .e_tracesig = NULL, 215 .e_sigcode = NULL, 216 .e_esigcode = NULL, 217 .e_sigobject = NULL, 218 .e_setregs = setregs, 219 .e_proc_exec = NULL, 220 .e_proc_fork = NULL, 221 .e_proc_exit = NULL, 222 .e_lwp_fork = NULL, 223 .e_lwp_exit = NULL, 224 #ifdef __HAVE_SYSCALL_INTERN 225 .e_syscall_intern = syscall_intern, 226 #else 227 .e_syscall = syscall, 228 #endif 229 .e_sysctlovly = NULL, 230 .e_fault = NULL, 231 .e_vm_default_addr = uvm_default_mapaddr, 232 .e_usertrap = NULL, 233 .e_ucsize = sizeof(ucontext_t), 234 .e_startlwp = startlwp 235 }; 236 237 /* 238 * Exec lock. Used to control access to execsw[] structures. 239 * This must not be static so that netbsd32 can access it, too. 240 */ 241 krwlock_t exec_lock; 242 243 static kmutex_t sigobject_lock; 244 245 /* 246 * Data used between a loadvm and execve part of an "exec" operation 247 */ 248 struct execve_data { 249 struct exec_package ed_pack; 250 struct pathbuf *ed_pathbuf; 251 struct vattr ed_attr; 252 struct ps_strings ed_arginfo; 253 char *ed_argp; 254 const char *ed_pathstring; 255 char *ed_resolvedpathbuf; 256 size_t ed_ps_strings_sz; 257 int ed_szsigcode; 258 size_t ed_argslen; 259 long ed_argc; 260 long ed_envc; 261 }; 262 263 /* 264 * data passed from parent lwp to child during a posix_spawn() 265 */ 266 struct spawn_exec_data { 267 struct execve_data sed_exec; 268 struct posix_spawn_file_actions 269 *sed_actions; 270 struct posix_spawnattr *sed_attrs; 271 struct proc *sed_parent; 272 kcondvar_t sed_cv_child_ready; 273 kmutex_t sed_mtx_child; 274 int sed_error; 275 volatile uint32_t sed_refcnt; 276 }; 277 278 static void * 279 exec_pool_alloc(struct pool *pp, int flags) 280 { 281 282 return (void *)uvm_km_alloc(kernel_map, NCARGS, 0, 283 UVM_KMF_PAGEABLE | UVM_KMF_WAITVA); 284 } 285 286 static void 287 exec_pool_free(struct pool *pp, void *addr) 288 { 289 290 uvm_km_free(kernel_map, (vaddr_t)addr, NCARGS, UVM_KMF_PAGEABLE); 291 } 292 293 static struct pool exec_pool; 294 295 static struct pool_allocator exec_palloc = { 296 .pa_alloc = exec_pool_alloc, 297 .pa_free = exec_pool_free, 298 .pa_pagesz = NCARGS 299 }; 300 301 /* 302 * check exec: 303 * given an "executable" described in the exec package's namei info, 304 * see what we can do with it. 305 * 306 * ON ENTRY: 307 * exec package with appropriate namei info 308 * lwp pointer of exec'ing lwp 309 * NO SELF-LOCKED VNODES 310 * 311 * ON EXIT: 312 * error: nothing held, etc. exec header still allocated. 313 * ok: filled exec package, executable's vnode (unlocked). 314 * 315 * EXEC SWITCH ENTRY: 316 * Locked vnode to check, exec package, proc. 317 * 318 * EXEC SWITCH EXIT: 319 * ok: return 0, filled exec package, executable's vnode (unlocked). 320 * error: destructive: 321 * everything deallocated execept exec header. 322 * non-destructive: 323 * error code, executable's vnode (unlocked), 324 * exec header unmodified. 325 */ 326 int 327 /*ARGSUSED*/ 328 check_exec(struct lwp *l, struct exec_package *epp, struct pathbuf *pb) 329 { 330 int error, i; 331 struct vnode *vp; 332 struct nameidata nd; 333 size_t resid; 334 335 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | TRYEMULROOT, pb); 336 337 /* first get the vnode */ 338 if ((error = namei(&nd)) != 0) 339 return error; 340 epp->ep_vp = vp = nd.ni_vp; 341 /* normally this can't fail */ 342 error = copystr(nd.ni_pnbuf, epp->ep_resolvedname, PATH_MAX, NULL); 343 KASSERT(error == 0); 344 345 #ifdef DIAGNOSTIC 346 /* paranoia (take this out once namei stuff stabilizes) */ 347 memset(nd.ni_pnbuf, '~', PATH_MAX); 348 #endif 349 350 /* check access and type */ 351 if (vp->v_type != VREG) { 352 error = EACCES; 353 goto bad1; 354 } 355 if ((error = VOP_ACCESS(vp, VEXEC, l->l_cred)) != 0) 356 goto bad1; 357 358 /* get attributes */ 359 if ((error = VOP_GETATTR(vp, epp->ep_vap, l->l_cred)) != 0) 360 goto bad1; 361 362 /* Check mount point */ 363 if (vp->v_mount->mnt_flag & MNT_NOEXEC) { 364 error = EACCES; 365 goto bad1; 366 } 367 if (vp->v_mount->mnt_flag & MNT_NOSUID) 368 epp->ep_vap->va_mode &= ~(S_ISUID | S_ISGID); 369 370 /* try to open it */ 371 if ((error = VOP_OPEN(vp, FREAD, l->l_cred)) != 0) 372 goto bad1; 373 374 /* unlock vp, since we need it unlocked from here on out. */ 375 VOP_UNLOCK(vp); 376 377 #if NVERIEXEC > 0 378 error = veriexec_verify(l, vp, epp->ep_resolvedname, 379 epp->ep_flags & EXEC_INDIR ? VERIEXEC_INDIRECT : VERIEXEC_DIRECT, 380 NULL); 381 if (error) 382 goto bad2; 383 #endif /* NVERIEXEC > 0 */ 384 385 #ifdef PAX_SEGVGUARD 386 error = pax_segvguard(l, vp, epp->ep_resolvedname, false); 387 if (error) 388 goto bad2; 389 #endif /* PAX_SEGVGUARD */ 390 391 /* now we have the file, get the exec header */ 392 error = vn_rdwr(UIO_READ, vp, epp->ep_hdr, epp->ep_hdrlen, 0, 393 UIO_SYSSPACE, 0, l->l_cred, &resid, NULL); 394 if (error) 395 goto bad2; 396 epp->ep_hdrvalid = epp->ep_hdrlen - resid; 397 398 /* 399 * Set up default address space limits. Can be overridden 400 * by individual exec packages. 401 * 402 * XXX probably should be all done in the exec packages. 403 */ 404 epp->ep_vm_minaddr = VM_MIN_ADDRESS; 405 epp->ep_vm_maxaddr = VM_MAXUSER_ADDRESS; 406 /* 407 * set up the vmcmds for creation of the process 408 * address space 409 */ 410 error = ENOEXEC; 411 for (i = 0; i < nexecs; i++) { 412 int newerror; 413 414 epp->ep_esch = execsw[i]; 415 newerror = (*execsw[i]->es_makecmds)(l, epp); 416 417 if (!newerror) { 418 /* Seems ok: check that entry point is not too high */ 419 if (epp->ep_entry > epp->ep_vm_maxaddr) { 420 #ifdef DIAGNOSTIC 421 printf("%s: rejecting %p due to " 422 "too high entry address (> %p)\n", 423 __func__, (void *)epp->ep_entry, 424 (void *)epp->ep_vm_maxaddr); 425 #endif 426 error = ENOEXEC; 427 break; 428 } 429 /* Seems ok: check that entry point is not too low */ 430 if (epp->ep_entry < epp->ep_vm_minaddr) { 431 #ifdef DIAGNOSTIC 432 printf("%s: rejecting %p due to " 433 "too low entry address (< %p)\n", 434 __func__, (void *)epp->ep_entry, 435 (void *)epp->ep_vm_minaddr); 436 #endif 437 error = ENOEXEC; 438 break; 439 } 440 441 /* check limits */ 442 if ((epp->ep_tsize > MAXTSIZ) || 443 (epp->ep_dsize > (u_quad_t)l->l_proc->p_rlimit 444 [RLIMIT_DATA].rlim_cur)) { 445 #ifdef DIAGNOSTIC 446 printf("%s: rejecting due to " 447 "limits (t=%llu > %llu || d=%llu > %llu)\n", 448 __func__, 449 (unsigned long long)epp->ep_tsize, 450 (unsigned long long)MAXTSIZ, 451 (unsigned long long)epp->ep_dsize, 452 (unsigned long long) 453 l->l_proc->p_rlimit[RLIMIT_DATA].rlim_cur); 454 #endif 455 error = ENOMEM; 456 break; 457 } 458 return 0; 459 } 460 461 if (epp->ep_emul_root != NULL) { 462 vrele(epp->ep_emul_root); 463 epp->ep_emul_root = NULL; 464 } 465 if (epp->ep_interp != NULL) { 466 vrele(epp->ep_interp); 467 epp->ep_interp = NULL; 468 } 469 470 /* make sure the first "interesting" error code is saved. */ 471 if (error == ENOEXEC) 472 error = newerror; 473 474 if (epp->ep_flags & EXEC_DESTR) 475 /* Error from "#!" code, tidied up by recursive call */ 476 return error; 477 } 478 479 /* not found, error */ 480 481 /* 482 * free any vmspace-creation commands, 483 * and release their references 484 */ 485 kill_vmcmds(&epp->ep_vmcmds); 486 487 bad2: 488 /* 489 * close and release the vnode, restore the old one, free the 490 * pathname buf, and punt. 491 */ 492 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 493 VOP_CLOSE(vp, FREAD, l->l_cred); 494 vput(vp); 495 return error; 496 497 bad1: 498 /* 499 * free the namei pathname buffer, and put the vnode 500 * (which we don't yet have open). 501 */ 502 vput(vp); /* was still locked */ 503 return error; 504 } 505 506 #ifdef __MACHINE_STACK_GROWS_UP 507 #define STACK_PTHREADSPACE NBPG 508 #else 509 #define STACK_PTHREADSPACE 0 510 #endif 511 512 static int 513 execve_fetch_element(char * const *array, size_t index, char **value) 514 { 515 return copyin(array + index, value, sizeof(*value)); 516 } 517 518 /* 519 * exec system call 520 */ 521 int 522 sys_execve(struct lwp *l, const struct sys_execve_args *uap, register_t *retval) 523 { 524 /* { 525 syscallarg(const char *) path; 526 syscallarg(char * const *) argp; 527 syscallarg(char * const *) envp; 528 } */ 529 530 return execve1(l, SCARG(uap, path), SCARG(uap, argp), 531 SCARG(uap, envp), execve_fetch_element); 532 } 533 534 int 535 sys_fexecve(struct lwp *l, const struct sys_fexecve_args *uap, 536 register_t *retval) 537 { 538 /* { 539 syscallarg(int) fd; 540 syscallarg(char * const *) argp; 541 syscallarg(char * const *) envp; 542 } */ 543 544 return ENOSYS; 545 } 546 547 /* 548 * Load modules to try and execute an image that we do not understand. 549 * If no execsw entries are present, we load those likely to be needed 550 * in order to run native images only. Otherwise, we autoload all 551 * possible modules that could let us run the binary. XXX lame 552 */ 553 static void 554 exec_autoload(void) 555 { 556 #ifdef MODULAR 557 static const char * const native[] = { 558 "exec_elf32", 559 "exec_elf64", 560 "exec_script", 561 NULL 562 }; 563 static const char * const compat[] = { 564 "exec_elf32", 565 "exec_elf64", 566 "exec_script", 567 "exec_aout", 568 "exec_coff", 569 "exec_ecoff", 570 "compat_aoutm68k", 571 "compat_freebsd", 572 "compat_ibcs2", 573 "compat_linux", 574 "compat_linux32", 575 "compat_netbsd32", 576 "compat_sunos", 577 "compat_sunos32", 578 "compat_svr4", 579 "compat_svr4_32", 580 "compat_ultrix", 581 NULL 582 }; 583 char const * const *list; 584 int i; 585 586 list = (nexecs == 0 ? native : compat); 587 for (i = 0; list[i] != NULL; i++) { 588 if (module_autoload(list[i], MODULE_CLASS_EXEC) != 0) { 589 continue; 590 } 591 yield(); 592 } 593 #endif 594 } 595 596 static struct pathbuf * 597 makepathbuf(struct lwp *l, const char *upath) 598 { 599 char *path, *bp; 600 size_t len; 601 int error; 602 struct cwdinfo *cwdi; 603 604 path = PNBUF_GET(); 605 error = copyinstr(upath, path, MAXPATHLEN, &len); 606 if (error) { 607 PNBUF_PUT(path); 608 DPRINTF(("%s: copyin path @%p %d\n", __func__, upath, error)); 609 return NULL; 610 } 611 612 if (path[0] == '/') 613 goto out; 614 615 len++; 616 if (len + 1 >= MAXPATHLEN) 617 goto out; 618 bp = path + MAXPATHLEN - len; 619 memmove(bp, path, len); 620 *(--bp) = '/'; 621 622 cwdi = l->l_proc->p_cwdi; 623 rw_enter(&cwdi->cwdi_lock, RW_READER); 624 error = getcwd_common(cwdi->cwdi_cdir, NULL, &bp, path, MAXPATHLEN / 2, 625 GETCWD_CHECK_ACCESS, l); 626 rw_exit(&cwdi->cwdi_lock); 627 628 if (error) { 629 DPRINTF(("%s: getcwd_common path %s %d\n", __func__, path, 630 error)); 631 goto out; 632 } 633 len = path + MAXPATHLEN - bp; 634 635 memmove(path, bp, len); 636 path[len] = '\0'; 637 out: 638 return pathbuf_assimilate(path); 639 } 640 641 static int 642 execve_loadvm(struct lwp *l, const char *path, char * const *args, 643 char * const *envs, execve_fetch_element_t fetch_element, 644 struct execve_data * restrict data) 645 { 646 struct exec_package * const epp = &data->ed_pack; 647 int error; 648 struct proc *p; 649 char *dp; 650 u_int modgen; 651 652 KASSERT(data != NULL); 653 654 p = l->l_proc; 655 modgen = 0; 656 657 SDT_PROBE(proc,,,exec, path, 0, 0, 0, 0); 658 659 /* 660 * Check if we have exceeded our number of processes limit. 661 * This is so that we handle the case where a root daemon 662 * forked, ran setuid to become the desired user and is trying 663 * to exec. The obvious place to do the reference counting check 664 * is setuid(), but we don't do the reference counting check there 665 * like other OS's do because then all the programs that use setuid() 666 * must be modified to check the return code of setuid() and exit(). 667 * It is dangerous to make setuid() fail, because it fails open and 668 * the program will continue to run as root. If we make it succeed 669 * and return an error code, again we are not enforcing the limit. 670 * The best place to enforce the limit is here, when the process tries 671 * to execute a new image, because eventually the process will need 672 * to call exec in order to do something useful. 673 */ 674 retry: 675 if (p->p_flag & PK_SUGID) { 676 if (kauth_authorize_process(l->l_cred, KAUTH_PROCESS_RLIMIT, 677 p, KAUTH_ARG(KAUTH_REQ_PROCESS_RLIMIT_BYPASS), 678 &p->p_rlimit[RLIMIT_NPROC], 679 KAUTH_ARG(RLIMIT_NPROC)) != 0 && 680 chgproccnt(kauth_cred_getuid(l->l_cred), 0) > 681 p->p_rlimit[RLIMIT_NPROC].rlim_cur) 682 return EAGAIN; 683 } 684 685 /* 686 * Drain existing references and forbid new ones. The process 687 * should be left alone until we're done here. This is necessary 688 * to avoid race conditions - e.g. in ptrace() - that might allow 689 * a local user to illicitly obtain elevated privileges. 690 */ 691 rw_enter(&p->p_reflock, RW_WRITER); 692 693 /* 694 * Init the namei data to point the file user's program name. 695 * This is done here rather than in check_exec(), so that it's 696 * possible to override this settings if any of makecmd/probe 697 * functions call check_exec() recursively - for example, 698 * see exec_script_makecmds(). 699 */ 700 data->ed_pathbuf = makepathbuf(l, path); 701 if (data->ed_pathbuf == NULL) 702 goto clrflg; 703 data->ed_pathstring = pathbuf_stringcopy_get(data->ed_pathbuf); 704 data->ed_resolvedpathbuf = PNBUF_GET(); 705 706 /* 707 * initialize the fields of the exec package. 708 */ 709 epp->ep_kname = data->ed_pathstring; 710 epp->ep_resolvedname = data->ed_resolvedpathbuf; 711 epp->ep_hdr = kmem_alloc(exec_maxhdrsz, KM_SLEEP); 712 epp->ep_hdrlen = exec_maxhdrsz; 713 epp->ep_hdrvalid = 0; 714 epp->ep_emul_arg = NULL; 715 epp->ep_emul_arg_free = NULL; 716 memset(&epp->ep_vmcmds, 0, sizeof(epp->ep_vmcmds)); 717 epp->ep_vap = &data->ed_attr; 718 epp->ep_flags = (p->p_flag & PK_32) ? EXEC_FROM32 : 0; 719 MD_TOPDOWN_INIT(epp); 720 epp->ep_emul_root = NULL; 721 epp->ep_interp = NULL; 722 epp->ep_esch = NULL; 723 epp->ep_pax_flags = 0; 724 memset(epp->ep_machine_arch, 0, sizeof(epp->ep_machine_arch)); 725 726 rw_enter(&exec_lock, RW_READER); 727 728 /* see if we can run it. */ 729 if ((error = check_exec(l, epp, data->ed_pathbuf)) != 0) { 730 if (error != ENOENT) { 731 DPRINTF(("%s: check exec failed %d\n", 732 __func__, error)); 733 } 734 goto freehdr; 735 } 736 737 /* allocate an argument buffer */ 738 data->ed_argp = pool_get(&exec_pool, PR_WAITOK); 739 KASSERT(data->ed_argp != NULL); 740 dp = data->ed_argp; 741 742 if ((error = copyinargs(data, args, envs, fetch_element, &dp)) != 0) { 743 goto bad; 744 } 745 746 /* 747 * Calculate the new stack size. 748 */ 749 750 #ifdef PAX_ASLR 751 #define ASLR_GAP(l) (pax_aslr_active(l) ? (cprng_fast32() % PAGE_SIZE) : 0) 752 #else 753 #define ASLR_GAP(l) 0 754 #endif 755 756 #ifdef __MACHINE_STACK_GROWS_UP 757 /* 758 * copyargs() fills argc/argv/envp from the lower address even on 759 * __MACHINE_STACK_GROWS_UP machines. Reserve a few words just below the SP 760 * so that _rtld() use it. 761 */ 762 #define RTLD_GAP 32 763 #else 764 #define RTLD_GAP 0 765 #endif 766 767 const size_t argenvstrlen = (char *)ALIGN(dp) - data->ed_argp; 768 769 data->ed_argslen = calcargs(data, argenvstrlen); 770 771 const size_t len = calcstack(data, ASLR_GAP(l) + RTLD_GAP); 772 773 if (len > epp->ep_ssize) { 774 /* in effect, compare to initial limit */ 775 DPRINTF(("%s: stack limit exceeded %zu\n", __func__, len)); 776 error = ENOMEM; 777 goto bad; 778 } 779 /* adjust "active stack depth" for process VSZ */ 780 epp->ep_ssize = len; 781 782 return 0; 783 784 bad: 785 /* free the vmspace-creation commands, and release their references */ 786 kill_vmcmds(&epp->ep_vmcmds); 787 /* kill any opened file descriptor, if necessary */ 788 if (epp->ep_flags & EXEC_HASFD) { 789 epp->ep_flags &= ~EXEC_HASFD; 790 fd_close(epp->ep_fd); 791 } 792 /* close and put the exec'd file */ 793 vn_lock(epp->ep_vp, LK_EXCLUSIVE | LK_RETRY); 794 VOP_CLOSE(epp->ep_vp, FREAD, l->l_cred); 795 vput(epp->ep_vp); 796 pool_put(&exec_pool, data->ed_argp); 797 798 freehdr: 799 kmem_free(epp->ep_hdr, epp->ep_hdrlen); 800 if (epp->ep_emul_root != NULL) 801 vrele(epp->ep_emul_root); 802 if (epp->ep_interp != NULL) 803 vrele(epp->ep_interp); 804 805 rw_exit(&exec_lock); 806 807 pathbuf_stringcopy_put(data->ed_pathbuf, data->ed_pathstring); 808 pathbuf_destroy(data->ed_pathbuf); 809 PNBUF_PUT(data->ed_resolvedpathbuf); 810 811 clrflg: 812 rw_exit(&p->p_reflock); 813 814 if (modgen != module_gen && error == ENOEXEC) { 815 modgen = module_gen; 816 exec_autoload(); 817 goto retry; 818 } 819 820 SDT_PROBE(proc,,,exec_failure, error, 0, 0, 0, 0); 821 return error; 822 } 823 824 static int 825 execve_dovmcmds(struct lwp *l, struct execve_data * restrict data) 826 { 827 struct exec_package * const epp = &data->ed_pack; 828 struct proc *p = l->l_proc; 829 struct exec_vmcmd *base_vcp; 830 int error = 0; 831 size_t i; 832 833 /* record proc's vnode, for use by procfs and others */ 834 if (p->p_textvp) 835 vrele(p->p_textvp); 836 vref(epp->ep_vp); 837 p->p_textvp = epp->ep_vp; 838 839 /* create the new process's VM space by running the vmcmds */ 840 KASSERTMSG(epp->ep_vmcmds.evs_used != 0, "%s: no vmcmds", __func__); 841 842 DUMPVMCMDS(epp, 0, 0); 843 844 base_vcp = NULL; 845 846 for (i = 0; i < epp->ep_vmcmds.evs_used && !error; i++) { 847 struct exec_vmcmd *vcp; 848 849 vcp = &epp->ep_vmcmds.evs_cmds[i]; 850 if (vcp->ev_flags & VMCMD_RELATIVE) { 851 KASSERTMSG(base_vcp != NULL, 852 "%s: relative vmcmd with no base", __func__); 853 KASSERTMSG((vcp->ev_flags & VMCMD_BASE) == 0, 854 "%s: illegal base & relative vmcmd", __func__); 855 vcp->ev_addr += base_vcp->ev_addr; 856 } 857 error = (*vcp->ev_proc)(l, vcp); 858 if (error) 859 DUMPVMCMDS(epp, i, error); 860 if (vcp->ev_flags & VMCMD_BASE) 861 base_vcp = vcp; 862 } 863 864 /* free the vmspace-creation commands, and release their references */ 865 kill_vmcmds(&epp->ep_vmcmds); 866 867 vn_lock(epp->ep_vp, LK_EXCLUSIVE | LK_RETRY); 868 VOP_CLOSE(epp->ep_vp, FREAD, l->l_cred); 869 vput(epp->ep_vp); 870 871 /* if an error happened, deallocate and punt */ 872 if (error != 0) { 873 DPRINTF(("%s: vmcmd %zu failed: %d\n", __func__, i - 1, error)); 874 } 875 return error; 876 } 877 878 static void 879 execve_free_data(struct execve_data *data) 880 { 881 struct exec_package * const epp = &data->ed_pack; 882 883 /* free the vmspace-creation commands, and release their references */ 884 kill_vmcmds(&epp->ep_vmcmds); 885 /* kill any opened file descriptor, if necessary */ 886 if (epp->ep_flags & EXEC_HASFD) { 887 epp->ep_flags &= ~EXEC_HASFD; 888 fd_close(epp->ep_fd); 889 } 890 891 /* close and put the exec'd file */ 892 vn_lock(epp->ep_vp, LK_EXCLUSIVE | LK_RETRY); 893 VOP_CLOSE(epp->ep_vp, FREAD, curlwp->l_cred); 894 vput(epp->ep_vp); 895 pool_put(&exec_pool, data->ed_argp); 896 897 kmem_free(epp->ep_hdr, epp->ep_hdrlen); 898 if (epp->ep_emul_root != NULL) 899 vrele(epp->ep_emul_root); 900 if (epp->ep_interp != NULL) 901 vrele(epp->ep_interp); 902 903 pathbuf_stringcopy_put(data->ed_pathbuf, data->ed_pathstring); 904 pathbuf_destroy(data->ed_pathbuf); 905 PNBUF_PUT(data->ed_resolvedpathbuf); 906 } 907 908 static void 909 pathexec(struct exec_package *epp, struct proc *p, const char *pathstring) 910 { 911 const char *commandname; 912 size_t commandlen; 913 char *path; 914 915 /* set command name & other accounting info */ 916 commandname = strrchr(epp->ep_resolvedname, '/'); 917 if (commandname != NULL) { 918 commandname++; 919 } else { 920 commandname = epp->ep_resolvedname; 921 } 922 commandlen = min(strlen(commandname), MAXCOMLEN); 923 (void)memcpy(p->p_comm, commandname, commandlen); 924 p->p_comm[commandlen] = '\0'; 925 926 927 /* 928 * If the path starts with /, we don't need to do any work. 929 * This handles the majority of the cases. 930 * In the future perhaps we could canonicalize it? 931 */ 932 if (pathstring[0] == '/') { 933 path = PNBUF_GET(); 934 (void)strlcpy(path, pathstring, MAXPATHLEN); 935 epp->ep_path = path; 936 } else 937 epp->ep_path = NULL; 938 } 939 940 /* XXX elsewhere */ 941 static int 942 credexec(struct lwp *l, struct vattr *attr) 943 { 944 struct proc *p = l->l_proc; 945 int error; 946 947 /* 948 * Deal with set[ug]id. MNT_NOSUID has already been used to disable 949 * s[ug]id. It's OK to check for PSL_TRACED here as we have blocked 950 * out additional references on the process for the moment. 951 */ 952 if ((p->p_slflag & PSL_TRACED) == 0 && 953 954 (((attr->va_mode & S_ISUID) != 0 && 955 kauth_cred_geteuid(l->l_cred) != attr->va_uid) || 956 957 ((attr->va_mode & S_ISGID) != 0 && 958 kauth_cred_getegid(l->l_cred) != attr->va_gid))) { 959 /* 960 * Mark the process as SUGID before we do 961 * anything that might block. 962 */ 963 proc_crmod_enter(); 964 proc_crmod_leave(NULL, NULL, true); 965 966 /* Make sure file descriptors 0..2 are in use. */ 967 if ((error = fd_checkstd()) != 0) { 968 DPRINTF(("%s: fdcheckstd failed %d\n", 969 __func__, error)); 970 return error; 971 } 972 973 /* 974 * Copy the credential so other references don't see our 975 * changes. 976 */ 977 l->l_cred = kauth_cred_copy(l->l_cred); 978 #ifdef KTRACE 979 /* 980 * If the persistent trace flag isn't set, turn off. 981 */ 982 if (p->p_tracep) { 983 mutex_enter(&ktrace_lock); 984 if (!(p->p_traceflag & KTRFAC_PERSISTENT)) 985 ktrderef(p); 986 mutex_exit(&ktrace_lock); 987 } 988 #endif 989 if (attr->va_mode & S_ISUID) 990 kauth_cred_seteuid(l->l_cred, attr->va_uid); 991 if (attr->va_mode & S_ISGID) 992 kauth_cred_setegid(l->l_cred, attr->va_gid); 993 } else { 994 if (kauth_cred_geteuid(l->l_cred) == 995 kauth_cred_getuid(l->l_cred) && 996 kauth_cred_getegid(l->l_cred) == 997 kauth_cred_getgid(l->l_cred)) 998 p->p_flag &= ~PK_SUGID; 999 } 1000 1001 /* 1002 * Copy the credential so other references don't see our changes. 1003 * Test to see if this is necessary first, since in the common case 1004 * we won't need a private reference. 1005 */ 1006 if (kauth_cred_geteuid(l->l_cred) != kauth_cred_getsvuid(l->l_cred) || 1007 kauth_cred_getegid(l->l_cred) != kauth_cred_getsvgid(l->l_cred)) { 1008 l->l_cred = kauth_cred_copy(l->l_cred); 1009 kauth_cred_setsvuid(l->l_cred, kauth_cred_geteuid(l->l_cred)); 1010 kauth_cred_setsvgid(l->l_cred, kauth_cred_getegid(l->l_cred)); 1011 } 1012 1013 /* Update the master credentials. */ 1014 if (l->l_cred != p->p_cred) { 1015 kauth_cred_t ocred; 1016 1017 kauth_cred_hold(l->l_cred); 1018 mutex_enter(p->p_lock); 1019 ocred = p->p_cred; 1020 p->p_cred = l->l_cred; 1021 mutex_exit(p->p_lock); 1022 kauth_cred_free(ocred); 1023 } 1024 1025 return 0; 1026 } 1027 1028 static void 1029 emulexec(struct lwp *l, struct exec_package *epp) 1030 { 1031 struct proc *p = l->l_proc; 1032 1033 /* The emulation root will usually have been found when we looked 1034 * for the elf interpreter (or similar), if not look now. */ 1035 if (epp->ep_esch->es_emul->e_path != NULL && 1036 epp->ep_emul_root == NULL) 1037 emul_find_root(l, epp); 1038 1039 /* Any old emulation root got removed by fdcloseexec */ 1040 rw_enter(&p->p_cwdi->cwdi_lock, RW_WRITER); 1041 p->p_cwdi->cwdi_edir = epp->ep_emul_root; 1042 rw_exit(&p->p_cwdi->cwdi_lock); 1043 epp->ep_emul_root = NULL; 1044 if (epp->ep_interp != NULL) 1045 vrele(epp->ep_interp); 1046 1047 /* 1048 * Call emulation specific exec hook. This can setup per-process 1049 * p->p_emuldata or do any other per-process stuff an emulation needs. 1050 * 1051 * If we are executing process of different emulation than the 1052 * original forked process, call e_proc_exit() of the old emulation 1053 * first, then e_proc_exec() of new emulation. If the emulation is 1054 * same, the exec hook code should deallocate any old emulation 1055 * resources held previously by this process. 1056 */ 1057 if (p->p_emul && p->p_emul->e_proc_exit 1058 && p->p_emul != epp->ep_esch->es_emul) 1059 (*p->p_emul->e_proc_exit)(p); 1060 1061 /* 1062 * This is now LWP 1. 1063 */ 1064 /* XXX elsewhere */ 1065 mutex_enter(p->p_lock); 1066 p->p_nlwpid = 1; 1067 l->l_lid = 1; 1068 mutex_exit(p->p_lock); 1069 1070 /* 1071 * Call exec hook. Emulation code may NOT store reference to anything 1072 * from &pack. 1073 */ 1074 if (epp->ep_esch->es_emul->e_proc_exec) 1075 (*epp->ep_esch->es_emul->e_proc_exec)(p, epp); 1076 1077 /* update p_emul, the old value is no longer needed */ 1078 p->p_emul = epp->ep_esch->es_emul; 1079 1080 /* ...and the same for p_execsw */ 1081 p->p_execsw = epp->ep_esch; 1082 1083 #ifdef __HAVE_SYSCALL_INTERN 1084 (*p->p_emul->e_syscall_intern)(p); 1085 #endif 1086 ktremul(); 1087 } 1088 1089 static int 1090 execve_runproc(struct lwp *l, struct execve_data * restrict data, 1091 bool no_local_exec_lock, bool is_spawn) 1092 { 1093 struct exec_package * const epp = &data->ed_pack; 1094 int error = 0; 1095 struct proc *p; 1096 1097 /* 1098 * In case of a posix_spawn operation, the child doing the exec 1099 * might not hold the reader lock on exec_lock, but the parent 1100 * will do this instead. 1101 */ 1102 KASSERT(no_local_exec_lock || rw_lock_held(&exec_lock)); 1103 KASSERT(!no_local_exec_lock || is_spawn); 1104 KASSERT(data != NULL); 1105 1106 p = l->l_proc; 1107 1108 /* Get rid of other LWPs. */ 1109 if (p->p_nlwps > 1) { 1110 mutex_enter(p->p_lock); 1111 exit_lwps(l); 1112 mutex_exit(p->p_lock); 1113 } 1114 KDASSERT(p->p_nlwps == 1); 1115 1116 /* Destroy any lwpctl info. */ 1117 if (p->p_lwpctl != NULL) 1118 lwp_ctl_exit(); 1119 1120 /* Remove POSIX timers */ 1121 timers_free(p, TIMERS_POSIX); 1122 1123 /* 1124 * Do whatever is necessary to prepare the address space 1125 * for remapping. Note that this might replace the current 1126 * vmspace with another! 1127 */ 1128 if (is_spawn) 1129 uvmspace_spawn(l, epp->ep_vm_minaddr, 1130 epp->ep_vm_maxaddr, 1131 epp->ep_flags & EXEC_TOPDOWN_VM); 1132 else 1133 uvmspace_exec(l, epp->ep_vm_minaddr, 1134 epp->ep_vm_maxaddr, 1135 epp->ep_flags & EXEC_TOPDOWN_VM); 1136 1137 struct vmspace *vm; 1138 vm = p->p_vmspace; 1139 vm->vm_taddr = (void *)epp->ep_taddr; 1140 vm->vm_tsize = btoc(epp->ep_tsize); 1141 vm->vm_daddr = (void*)epp->ep_daddr; 1142 vm->vm_dsize = btoc(epp->ep_dsize); 1143 vm->vm_ssize = btoc(epp->ep_ssize); 1144 vm->vm_issize = 0; 1145 vm->vm_maxsaddr = (void *)epp->ep_maxsaddr; 1146 vm->vm_minsaddr = (void *)epp->ep_minsaddr; 1147 1148 #ifdef PAX_ASLR 1149 pax_aslr_init_vm(l, vm); 1150 #endif /* PAX_ASLR */ 1151 1152 /* Now map address space. */ 1153 error = execve_dovmcmds(l, data); 1154 if (error != 0) 1155 goto exec_abort; 1156 1157 pathexec(epp, p, data->ed_pathstring); 1158 1159 char * const newstack = STACK_GROW(vm->vm_minsaddr, epp->ep_ssize); 1160 1161 error = copyoutargs(data, l, newstack); 1162 if (error != 0) 1163 goto exec_abort; 1164 1165 cwdexec(p); 1166 fd_closeexec(); /* handle close on exec */ 1167 1168 if (__predict_false(ktrace_on)) 1169 fd_ktrexecfd(); 1170 1171 execsigs(p); /* reset catched signals */ 1172 1173 mutex_enter(p->p_lock); 1174 l->l_ctxlink = NULL; /* reset ucontext link */ 1175 p->p_acflag &= ~AFORK; 1176 p->p_flag |= PK_EXEC; 1177 mutex_exit(p->p_lock); 1178 1179 /* 1180 * Stop profiling. 1181 */ 1182 if ((p->p_stflag & PST_PROFIL) != 0) { 1183 mutex_spin_enter(&p->p_stmutex); 1184 stopprofclock(p); 1185 mutex_spin_exit(&p->p_stmutex); 1186 } 1187 1188 /* 1189 * It's OK to test PL_PPWAIT unlocked here, as other LWPs have 1190 * exited and exec()/exit() are the only places it will be cleared. 1191 */ 1192 if ((p->p_lflag & PL_PPWAIT) != 0) { 1193 #if 0 1194 lwp_t *lp; 1195 1196 mutex_enter(proc_lock); 1197 lp = p->p_vforklwp; 1198 p->p_vforklwp = NULL; 1199 1200 l->l_lwpctl = NULL; /* was on loan from blocked parent */ 1201 p->p_lflag &= ~PL_PPWAIT; 1202 1203 lp->l_pflag &= ~LP_VFORKWAIT; /* XXX */ 1204 cv_broadcast(&lp->l_waitcv); 1205 mutex_exit(proc_lock); 1206 #else 1207 mutex_enter(proc_lock); 1208 l->l_lwpctl = NULL; /* was on loan from blocked parent */ 1209 p->p_lflag &= ~PL_PPWAIT; 1210 cv_broadcast(&p->p_pptr->p_waitcv); 1211 mutex_exit(proc_lock); 1212 #endif 1213 } 1214 1215 error = credexec(l, &data->ed_attr); 1216 if (error) 1217 goto exec_abort; 1218 1219 #if defined(__HAVE_RAS) 1220 /* 1221 * Remove all RASs from the address space. 1222 */ 1223 ras_purgeall(); 1224 #endif 1225 1226 doexechooks(p); 1227 1228 /* 1229 * Set initial SP at the top of the stack. 1230 * 1231 * Note that on machines where stack grows up (e.g. hppa), SP points to 1232 * the end of arg/env strings. Userland guesses the address of argc 1233 * via ps_strings::ps_argvstr. 1234 */ 1235 1236 /* Setup new registers and do misc. setup. */ 1237 (*epp->ep_esch->es_emul->e_setregs)(l, epp, (vaddr_t)newstack); 1238 if (epp->ep_esch->es_setregs) 1239 (*epp->ep_esch->es_setregs)(l, epp, (vaddr_t)newstack); 1240 1241 /* Provide a consistent LWP private setting */ 1242 (void)lwp_setprivate(l, NULL); 1243 1244 /* Discard all PCU state; need to start fresh */ 1245 pcu_discard_all(l); 1246 1247 /* map the process's signal trampoline code */ 1248 if ((error = exec_sigcode_map(p, epp->ep_esch->es_emul)) != 0) { 1249 DPRINTF(("%s: map sigcode failed %d\n", __func__, error)); 1250 goto exec_abort; 1251 } 1252 1253 pool_put(&exec_pool, data->ed_argp); 1254 1255 /* notify others that we exec'd */ 1256 KNOTE(&p->p_klist, NOTE_EXEC); 1257 1258 kmem_free(epp->ep_hdr, epp->ep_hdrlen); 1259 1260 SDT_PROBE(proc,,,exec_success, epp->ep_kname, 0, 0, 0, 0); 1261 1262 emulexec(l, epp); 1263 1264 /* Allow new references from the debugger/procfs. */ 1265 rw_exit(&p->p_reflock); 1266 if (!no_local_exec_lock) 1267 rw_exit(&exec_lock); 1268 1269 mutex_enter(proc_lock); 1270 1271 if ((p->p_slflag & (PSL_TRACED|PSL_SYSCALL)) == PSL_TRACED) { 1272 ksiginfo_t ksi; 1273 1274 KSI_INIT_EMPTY(&ksi); 1275 ksi.ksi_signo = SIGTRAP; 1276 ksi.ksi_lid = l->l_lid; 1277 kpsignal(p, &ksi, NULL); 1278 } 1279 1280 if (p->p_sflag & PS_STOPEXEC) { 1281 ksiginfoq_t kq; 1282 1283 KERNEL_UNLOCK_ALL(l, &l->l_biglocks); 1284 p->p_pptr->p_nstopchild++; 1285 p->p_pptr->p_waited = 0; 1286 mutex_enter(p->p_lock); 1287 ksiginfo_queue_init(&kq); 1288 sigclearall(p, &contsigmask, &kq); 1289 lwp_lock(l); 1290 l->l_stat = LSSTOP; 1291 p->p_stat = SSTOP; 1292 p->p_nrlwps--; 1293 lwp_unlock(l); 1294 mutex_exit(p->p_lock); 1295 mutex_exit(proc_lock); 1296 lwp_lock(l); 1297 mi_switch(l); 1298 ksiginfo_queue_drain(&kq); 1299 KERNEL_LOCK(l->l_biglocks, l); 1300 } else { 1301 mutex_exit(proc_lock); 1302 } 1303 1304 pathbuf_stringcopy_put(data->ed_pathbuf, data->ed_pathstring); 1305 pathbuf_destroy(data->ed_pathbuf); 1306 PNBUF_PUT(data->ed_resolvedpathbuf); 1307 DPRINTF(("%s finished\n", __func__)); 1308 return EJUSTRETURN; 1309 1310 exec_abort: 1311 SDT_PROBE(proc,,,exec_failure, error, 0, 0, 0, 0); 1312 rw_exit(&p->p_reflock); 1313 if (!no_local_exec_lock) 1314 rw_exit(&exec_lock); 1315 1316 pathbuf_stringcopy_put(data->ed_pathbuf, data->ed_pathstring); 1317 pathbuf_destroy(data->ed_pathbuf); 1318 PNBUF_PUT(data->ed_resolvedpathbuf); 1319 1320 /* 1321 * the old process doesn't exist anymore. exit gracefully. 1322 * get rid of the (new) address space we have created, if any, get rid 1323 * of our namei data and vnode, and exit noting failure 1324 */ 1325 uvm_deallocate(&vm->vm_map, VM_MIN_ADDRESS, 1326 VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS); 1327 1328 exec_free_emul_arg(epp); 1329 pool_put(&exec_pool, data->ed_argp); 1330 kmem_free(epp->ep_hdr, epp->ep_hdrlen); 1331 if (epp->ep_emul_root != NULL) 1332 vrele(epp->ep_emul_root); 1333 if (epp->ep_interp != NULL) 1334 vrele(epp->ep_interp); 1335 1336 /* Acquire the sched-state mutex (exit1() will release it). */ 1337 if (!is_spawn) { 1338 mutex_enter(p->p_lock); 1339 exit1(l, W_EXITCODE(error, SIGABRT)); 1340 } 1341 1342 return error; 1343 } 1344 1345 int 1346 execve1(struct lwp *l, const char *path, char * const *args, 1347 char * const *envs, execve_fetch_element_t fetch_element) 1348 { 1349 struct execve_data data; 1350 int error; 1351 1352 error = execve_loadvm(l, path, args, envs, fetch_element, &data); 1353 if (error) 1354 return error; 1355 error = execve_runproc(l, &data, false, false); 1356 return error; 1357 } 1358 1359 static size_t 1360 fromptrsz(const struct exec_package *epp) 1361 { 1362 return (epp->ep_flags & EXEC_FROM32) ? sizeof(int) : sizeof(char *); 1363 } 1364 1365 static size_t 1366 ptrsz(const struct exec_package *epp) 1367 { 1368 return (epp->ep_flags & EXEC_32) ? sizeof(int) : sizeof(char *); 1369 } 1370 1371 static size_t 1372 calcargs(struct execve_data * restrict data, const size_t argenvstrlen) 1373 { 1374 struct exec_package * const epp = &data->ed_pack; 1375 1376 const size_t nargenvptrs = 1377 1 + /* long argc */ 1378 data->ed_argc + /* char *argv[] */ 1379 1 + /* \0 */ 1380 data->ed_envc + /* char *env[] */ 1381 1 + /* \0 */ 1382 epp->ep_esch->es_arglen; /* auxinfo */ 1383 1384 return (nargenvptrs * ptrsz(epp)) + argenvstrlen; 1385 } 1386 1387 static size_t 1388 calcstack(struct execve_data * restrict data, const size_t gaplen) 1389 { 1390 struct exec_package * const epp = &data->ed_pack; 1391 1392 data->ed_szsigcode = epp->ep_esch->es_emul->e_esigcode - 1393 epp->ep_esch->es_emul->e_sigcode; 1394 1395 data->ed_ps_strings_sz = (epp->ep_flags & EXEC_32) ? 1396 sizeof(struct ps_strings32) : sizeof(struct ps_strings); 1397 1398 const size_t sigcode_psstr_sz = 1399 data->ed_szsigcode + /* sigcode */ 1400 data->ed_ps_strings_sz + /* ps_strings */ 1401 STACK_PTHREADSPACE; /* pthread space */ 1402 1403 const size_t stacklen = 1404 data->ed_argslen + 1405 gaplen + 1406 sigcode_psstr_sz; 1407 1408 /* make the stack "safely" aligned */ 1409 return STACK_LEN_ALIGN(stacklen, STACK_ALIGNBYTES); 1410 } 1411 1412 static int 1413 copyoutargs(struct execve_data * restrict data, struct lwp *l, 1414 char * const newstack) 1415 { 1416 struct exec_package * const epp = &data->ed_pack; 1417 struct proc *p = l->l_proc; 1418 int error; 1419 1420 /* remember information about the process */ 1421 data->ed_arginfo.ps_nargvstr = data->ed_argc; 1422 data->ed_arginfo.ps_nenvstr = data->ed_envc; 1423 1424 /* 1425 * Allocate the stack address passed to the newly execve()'ed process. 1426 * 1427 * The new stack address will be set to the SP (stack pointer) register 1428 * in setregs(). 1429 */ 1430 1431 char *newargs = STACK_ALLOC( 1432 STACK_SHRINK(newstack, data->ed_argslen), data->ed_argslen); 1433 1434 error = (*epp->ep_esch->es_copyargs)(l, epp, 1435 &data->ed_arginfo, &newargs, data->ed_argp); 1436 1437 if (epp->ep_path) { 1438 PNBUF_PUT(epp->ep_path); 1439 epp->ep_path = NULL; 1440 } 1441 if (error) { 1442 DPRINTF(("%s: copyargs failed %d\n", __func__, error)); 1443 return error; 1444 } 1445 1446 error = copyoutpsstrs(data, p); 1447 if (error != 0) 1448 return error; 1449 1450 return 0; 1451 } 1452 1453 static int 1454 copyoutpsstrs(struct execve_data * restrict data, struct proc *p) 1455 { 1456 struct exec_package * const epp = &data->ed_pack; 1457 struct ps_strings32 arginfo32; 1458 void *aip; 1459 int error; 1460 1461 /* fill process ps_strings info */ 1462 p->p_psstrp = (vaddr_t)STACK_ALLOC(STACK_GROW(epp->ep_minsaddr, 1463 STACK_PTHREADSPACE), data->ed_ps_strings_sz); 1464 1465 if (epp->ep_flags & EXEC_32) { 1466 aip = &arginfo32; 1467 arginfo32.ps_argvstr = (vaddr_t)data->ed_arginfo.ps_argvstr; 1468 arginfo32.ps_nargvstr = data->ed_arginfo.ps_nargvstr; 1469 arginfo32.ps_envstr = (vaddr_t)data->ed_arginfo.ps_envstr; 1470 arginfo32.ps_nenvstr = data->ed_arginfo.ps_nenvstr; 1471 } else 1472 aip = &data->ed_arginfo; 1473 1474 /* copy out the process's ps_strings structure */ 1475 if ((error = copyout(aip, (void *)p->p_psstrp, data->ed_ps_strings_sz)) 1476 != 0) { 1477 DPRINTF(("%s: ps_strings copyout %p->%p size %zu failed\n", 1478 __func__, aip, (void *)p->p_psstrp, data->ed_ps_strings_sz)); 1479 return error; 1480 } 1481 1482 return 0; 1483 } 1484 1485 static int 1486 copyinargs(struct execve_data * restrict data, char * const *args, 1487 char * const *envs, execve_fetch_element_t fetch_element, char **dpp) 1488 { 1489 struct exec_package * const epp = &data->ed_pack; 1490 char *dp; 1491 size_t i; 1492 int error; 1493 1494 dp = *dpp; 1495 1496 data->ed_argc = 0; 1497 1498 /* copy the fake args list, if there's one, freeing it as we go */ 1499 if (epp->ep_flags & EXEC_HASARGL) { 1500 struct exec_fakearg *fa = epp->ep_fa; 1501 1502 while (fa->fa_arg != NULL) { 1503 const size_t maxlen = ARG_MAX - (dp - data->ed_argp); 1504 size_t len; 1505 1506 len = strlcpy(dp, fa->fa_arg, maxlen); 1507 /* Count NUL into len. */ 1508 if (len < maxlen) 1509 len++; 1510 else { 1511 while (fa->fa_arg != NULL) { 1512 kmem_free(fa->fa_arg, fa->fa_len); 1513 fa++; 1514 } 1515 kmem_free(epp->ep_fa, epp->ep_fa_len); 1516 epp->ep_flags &= ~EXEC_HASARGL; 1517 return E2BIG; 1518 } 1519 ktrexecarg(fa->fa_arg, len - 1); 1520 dp += len; 1521 1522 kmem_free(fa->fa_arg, fa->fa_len); 1523 fa++; 1524 data->ed_argc++; 1525 } 1526 kmem_free(epp->ep_fa, epp->ep_fa_len); 1527 epp->ep_flags &= ~EXEC_HASARGL; 1528 } 1529 1530 /* 1531 * Read and count argument strings from user. 1532 */ 1533 1534 if (args == NULL) { 1535 DPRINTF(("%s: null args\n", __func__)); 1536 return EINVAL; 1537 } 1538 if (epp->ep_flags & EXEC_SKIPARG) 1539 args = (const void *)((const char *)args + fromptrsz(epp)); 1540 i = 0; 1541 error = copyinargstrs(data, args, fetch_element, &dp, &i, ktr_execarg); 1542 if (error != 0) { 1543 DPRINTF(("%s: copyin arg %d\n", __func__, error)); 1544 return error; 1545 } 1546 data->ed_argc += i; 1547 1548 /* 1549 * Read and count environment strings from user. 1550 */ 1551 1552 data->ed_envc = 0; 1553 /* environment need not be there */ 1554 if (envs == NULL) 1555 goto done; 1556 i = 0; 1557 error = copyinargstrs(data, envs, fetch_element, &dp, &i, ktr_execenv); 1558 if (error != 0) { 1559 DPRINTF(("%s: copyin env %d\n", __func__, error)); 1560 return error; 1561 } 1562 data->ed_envc += i; 1563 1564 done: 1565 *dpp = dp; 1566 1567 return 0; 1568 } 1569 1570 static int 1571 copyinargstrs(struct execve_data * restrict data, char * const *strs, 1572 execve_fetch_element_t fetch_element, char **dpp, size_t *ip, 1573 void (*ktr)(const void *, size_t)) 1574 { 1575 char *dp, *sp; 1576 size_t i; 1577 int error; 1578 1579 dp = *dpp; 1580 1581 i = 0; 1582 while (1) { 1583 const size_t maxlen = ARG_MAX - (dp - data->ed_argp); 1584 size_t len; 1585 1586 if ((error = (*fetch_element)(strs, i, &sp)) != 0) { 1587 return error; 1588 } 1589 if (!sp) 1590 break; 1591 if ((error = copyinstr(sp, dp, maxlen, &len)) != 0) { 1592 if (error == ENAMETOOLONG) 1593 error = E2BIG; 1594 return error; 1595 } 1596 if (__predict_false(ktrace_on)) 1597 (*ktr)(dp, len - 1); 1598 dp += len; 1599 i++; 1600 } 1601 1602 *dpp = dp; 1603 *ip = i; 1604 1605 return 0; 1606 } 1607 1608 /* 1609 * Copy argv and env strings from kernel buffer (argp) to the new stack. 1610 * Those strings are located just after auxinfo. 1611 */ 1612 int 1613 copyargs(struct lwp *l, struct exec_package *pack, struct ps_strings *arginfo, 1614 char **stackp, void *argp) 1615 { 1616 char **cpp, *dp, *sp; 1617 size_t len; 1618 void *nullp; 1619 long argc, envc; 1620 int error; 1621 1622 cpp = (char **)*stackp; 1623 nullp = NULL; 1624 argc = arginfo->ps_nargvstr; 1625 envc = arginfo->ps_nenvstr; 1626 1627 /* argc on stack is long */ 1628 CTASSERT(sizeof(*cpp) == sizeof(argc)); 1629 1630 dp = (char *)(cpp + 1631 1 + /* long argc */ 1632 argc + /* char *argv[] */ 1633 1 + /* \0 */ 1634 envc + /* char *env[] */ 1635 1 + /* \0 */ 1636 /* XXX auxinfo multiplied by ptr size? */ 1637 pack->ep_esch->es_arglen); /* auxinfo */ 1638 sp = argp; 1639 1640 if ((error = copyout(&argc, cpp++, sizeof(argc))) != 0) { 1641 COPYPRINTF("", cpp - 1, sizeof(argc)); 1642 return error; 1643 } 1644 1645 /* XXX don't copy them out, remap them! */ 1646 arginfo->ps_argvstr = cpp; /* remember location of argv for later */ 1647 1648 for (; --argc >= 0; sp += len, dp += len) { 1649 if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0) { 1650 COPYPRINTF("", cpp - 1, sizeof(dp)); 1651 return error; 1652 } 1653 if ((error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0) { 1654 COPYPRINTF("str", dp, (size_t)ARG_MAX); 1655 return error; 1656 } 1657 } 1658 1659 if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0) { 1660 COPYPRINTF("", cpp - 1, sizeof(nullp)); 1661 return error; 1662 } 1663 1664 arginfo->ps_envstr = cpp; /* remember location of envp for later */ 1665 1666 for (; --envc >= 0; sp += len, dp += len) { 1667 if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0) { 1668 COPYPRINTF("", cpp - 1, sizeof(dp)); 1669 return error; 1670 } 1671 if ((error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0) { 1672 COPYPRINTF("str", dp, (size_t)ARG_MAX); 1673 return error; 1674 } 1675 1676 } 1677 1678 if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0) { 1679 COPYPRINTF("", cpp - 1, sizeof(nullp)); 1680 return error; 1681 } 1682 1683 *stackp = (char *)cpp; 1684 return 0; 1685 } 1686 1687 1688 /* 1689 * Add execsw[] entries. 1690 */ 1691 int 1692 exec_add(struct execsw *esp, int count) 1693 { 1694 struct exec_entry *it; 1695 int i; 1696 1697 if (count == 0) { 1698 return 0; 1699 } 1700 1701 /* Check for duplicates. */ 1702 rw_enter(&exec_lock, RW_WRITER); 1703 for (i = 0; i < count; i++) { 1704 LIST_FOREACH(it, &ex_head, ex_list) { 1705 /* assume unique (makecmds, probe_func, emulation) */ 1706 if (it->ex_sw->es_makecmds == esp[i].es_makecmds && 1707 it->ex_sw->u.elf_probe_func == 1708 esp[i].u.elf_probe_func && 1709 it->ex_sw->es_emul == esp[i].es_emul) { 1710 rw_exit(&exec_lock); 1711 return EEXIST; 1712 } 1713 } 1714 } 1715 1716 /* Allocate new entries. */ 1717 for (i = 0; i < count; i++) { 1718 it = kmem_alloc(sizeof(*it), KM_SLEEP); 1719 it->ex_sw = &esp[i]; 1720 LIST_INSERT_HEAD(&ex_head, it, ex_list); 1721 } 1722 1723 /* update execsw[] */ 1724 exec_init(0); 1725 rw_exit(&exec_lock); 1726 return 0; 1727 } 1728 1729 /* 1730 * Remove execsw[] entry. 1731 */ 1732 int 1733 exec_remove(struct execsw *esp, int count) 1734 { 1735 struct exec_entry *it, *next; 1736 int i; 1737 const struct proclist_desc *pd; 1738 proc_t *p; 1739 1740 if (count == 0) { 1741 return 0; 1742 } 1743 1744 /* Abort if any are busy. */ 1745 rw_enter(&exec_lock, RW_WRITER); 1746 for (i = 0; i < count; i++) { 1747 mutex_enter(proc_lock); 1748 for (pd = proclists; pd->pd_list != NULL; pd++) { 1749 PROCLIST_FOREACH(p, pd->pd_list) { 1750 if (p->p_execsw == &esp[i]) { 1751 mutex_exit(proc_lock); 1752 rw_exit(&exec_lock); 1753 return EBUSY; 1754 } 1755 } 1756 } 1757 mutex_exit(proc_lock); 1758 } 1759 1760 /* None are busy, so remove them all. */ 1761 for (i = 0; i < count; i++) { 1762 for (it = LIST_FIRST(&ex_head); it != NULL; it = next) { 1763 next = LIST_NEXT(it, ex_list); 1764 if (it->ex_sw == &esp[i]) { 1765 LIST_REMOVE(it, ex_list); 1766 kmem_free(it, sizeof(*it)); 1767 break; 1768 } 1769 } 1770 } 1771 1772 /* update execsw[] */ 1773 exec_init(0); 1774 rw_exit(&exec_lock); 1775 return 0; 1776 } 1777 1778 /* 1779 * Initialize exec structures. If init_boot is true, also does necessary 1780 * one-time initialization (it's called from main() that way). 1781 * Once system is multiuser, this should be called with exec_lock held, 1782 * i.e. via exec_{add|remove}(). 1783 */ 1784 int 1785 exec_init(int init_boot) 1786 { 1787 const struct execsw **sw; 1788 struct exec_entry *ex; 1789 SLIST_HEAD(,exec_entry) first; 1790 SLIST_HEAD(,exec_entry) any; 1791 SLIST_HEAD(,exec_entry) last; 1792 int i, sz; 1793 1794 if (init_boot) { 1795 /* do one-time initializations */ 1796 rw_init(&exec_lock); 1797 mutex_init(&sigobject_lock, MUTEX_DEFAULT, IPL_NONE); 1798 pool_init(&exec_pool, NCARGS, 0, 0, PR_NOALIGN|PR_NOTOUCH, 1799 "execargs", &exec_palloc, IPL_NONE); 1800 pool_sethardlimit(&exec_pool, maxexec, "should not happen", 0); 1801 } else { 1802 KASSERT(rw_write_held(&exec_lock)); 1803 } 1804 1805 /* Sort each entry onto the appropriate queue. */ 1806 SLIST_INIT(&first); 1807 SLIST_INIT(&any); 1808 SLIST_INIT(&last); 1809 sz = 0; 1810 LIST_FOREACH(ex, &ex_head, ex_list) { 1811 switch(ex->ex_sw->es_prio) { 1812 case EXECSW_PRIO_FIRST: 1813 SLIST_INSERT_HEAD(&first, ex, ex_slist); 1814 break; 1815 case EXECSW_PRIO_ANY: 1816 SLIST_INSERT_HEAD(&any, ex, ex_slist); 1817 break; 1818 case EXECSW_PRIO_LAST: 1819 SLIST_INSERT_HEAD(&last, ex, ex_slist); 1820 break; 1821 default: 1822 panic("%s", __func__); 1823 break; 1824 } 1825 sz++; 1826 } 1827 1828 /* 1829 * Create new execsw[]. Ensure we do not try a zero-sized 1830 * allocation. 1831 */ 1832 sw = kmem_alloc(sz * sizeof(struct execsw *) + 1, KM_SLEEP); 1833 i = 0; 1834 SLIST_FOREACH(ex, &first, ex_slist) { 1835 sw[i++] = ex->ex_sw; 1836 } 1837 SLIST_FOREACH(ex, &any, ex_slist) { 1838 sw[i++] = ex->ex_sw; 1839 } 1840 SLIST_FOREACH(ex, &last, ex_slist) { 1841 sw[i++] = ex->ex_sw; 1842 } 1843 1844 /* Replace old execsw[] and free used memory. */ 1845 if (execsw != NULL) { 1846 kmem_free(__UNCONST(execsw), 1847 nexecs * sizeof(struct execsw *) + 1); 1848 } 1849 execsw = sw; 1850 nexecs = sz; 1851 1852 /* Figure out the maximum size of an exec header. */ 1853 exec_maxhdrsz = sizeof(int); 1854 for (i = 0; i < nexecs; i++) { 1855 if (execsw[i]->es_hdrsz > exec_maxhdrsz) 1856 exec_maxhdrsz = execsw[i]->es_hdrsz; 1857 } 1858 1859 return 0; 1860 } 1861 1862 static int 1863 exec_sigcode_map(struct proc *p, const struct emul *e) 1864 { 1865 vaddr_t va; 1866 vsize_t sz; 1867 int error; 1868 struct uvm_object *uobj; 1869 1870 sz = (vaddr_t)e->e_esigcode - (vaddr_t)e->e_sigcode; 1871 1872 if (e->e_sigobject == NULL || sz == 0) { 1873 return 0; 1874 } 1875 1876 /* 1877 * If we don't have a sigobject for this emulation, create one. 1878 * 1879 * sigobject is an anonymous memory object (just like SYSV shared 1880 * memory) that we keep a permanent reference to and that we map 1881 * in all processes that need this sigcode. The creation is simple, 1882 * we create an object, add a permanent reference to it, map it in 1883 * kernel space, copy out the sigcode to it and unmap it. 1884 * We map it with PROT_READ|PROT_EXEC into the process just 1885 * the way sys_mmap() would map it. 1886 */ 1887 1888 uobj = *e->e_sigobject; 1889 if (uobj == NULL) { 1890 mutex_enter(&sigobject_lock); 1891 if ((uobj = *e->e_sigobject) == NULL) { 1892 uobj = uao_create(sz, 0); 1893 (*uobj->pgops->pgo_reference)(uobj); 1894 va = vm_map_min(kernel_map); 1895 if ((error = uvm_map(kernel_map, &va, round_page(sz), 1896 uobj, 0, 0, 1897 UVM_MAPFLAG(UVM_PROT_RW, UVM_PROT_RW, 1898 UVM_INH_SHARE, UVM_ADV_RANDOM, 0)))) { 1899 printf("kernel mapping failed %d\n", error); 1900 (*uobj->pgops->pgo_detach)(uobj); 1901 mutex_exit(&sigobject_lock); 1902 return error; 1903 } 1904 memcpy((void *)va, e->e_sigcode, sz); 1905 #ifdef PMAP_NEED_PROCWR 1906 pmap_procwr(&proc0, va, sz); 1907 #endif 1908 uvm_unmap(kernel_map, va, va + round_page(sz)); 1909 *e->e_sigobject = uobj; 1910 } 1911 mutex_exit(&sigobject_lock); 1912 } 1913 1914 /* Just a hint to uvm_map where to put it. */ 1915 va = e->e_vm_default_addr(p, (vaddr_t)p->p_vmspace->vm_daddr, 1916 round_page(sz)); 1917 1918 #ifdef __alpha__ 1919 /* 1920 * Tru64 puts /sbin/loader at the end of user virtual memory, 1921 * which causes the above calculation to put the sigcode at 1922 * an invalid address. Put it just below the text instead. 1923 */ 1924 if (va == (vaddr_t)vm_map_max(&p->p_vmspace->vm_map)) { 1925 va = (vaddr_t)p->p_vmspace->vm_taddr - round_page(sz); 1926 } 1927 #endif 1928 1929 (*uobj->pgops->pgo_reference)(uobj); 1930 error = uvm_map(&p->p_vmspace->vm_map, &va, round_page(sz), 1931 uobj, 0, 0, 1932 UVM_MAPFLAG(UVM_PROT_RX, UVM_PROT_RX, UVM_INH_SHARE, 1933 UVM_ADV_RANDOM, 0)); 1934 if (error) { 1935 DPRINTF(("%s, %d: map %p " 1936 "uvm_map %#"PRIxVSIZE"@%#"PRIxVADDR" failed %d\n", 1937 __func__, __LINE__, &p->p_vmspace->vm_map, round_page(sz), 1938 va, error)); 1939 (*uobj->pgops->pgo_detach)(uobj); 1940 return error; 1941 } 1942 p->p_sigctx.ps_sigcode = (void *)va; 1943 return 0; 1944 } 1945 1946 /* 1947 * Release a refcount on spawn_exec_data and destroy memory, if this 1948 * was the last one. 1949 */ 1950 static void 1951 spawn_exec_data_release(struct spawn_exec_data *data) 1952 { 1953 if (atomic_dec_32_nv(&data->sed_refcnt) != 0) 1954 return; 1955 1956 cv_destroy(&data->sed_cv_child_ready); 1957 mutex_destroy(&data->sed_mtx_child); 1958 1959 if (data->sed_actions) 1960 posix_spawn_fa_free(data->sed_actions, 1961 data->sed_actions->len); 1962 if (data->sed_attrs) 1963 kmem_free(data->sed_attrs, 1964 sizeof(*data->sed_attrs)); 1965 kmem_free(data, sizeof(*data)); 1966 } 1967 1968 /* 1969 * A child lwp of a posix_spawn operation starts here and ends up in 1970 * cpu_spawn_return, dealing with all filedescriptor and scheduler 1971 * manipulations in between. 1972 * The parent waits for the child, as it is not clear whether the child 1973 * will be able to acquire its own exec_lock. If it can, the parent can 1974 * be released early and continue running in parallel. If not (or if the 1975 * magic debug flag is passed in the scheduler attribute struct), the 1976 * child rides on the parent's exec lock until it is ready to return to 1977 * to userland - and only then releases the parent. This method loses 1978 * concurrency, but improves error reporting. 1979 */ 1980 static void 1981 spawn_return(void *arg) 1982 { 1983 struct spawn_exec_data *spawn_data = arg; 1984 struct lwp *l = curlwp; 1985 int error, newfd; 1986 size_t i; 1987 const struct posix_spawn_file_actions_entry *fae; 1988 pid_t ppid; 1989 register_t retval; 1990 bool have_reflock; 1991 bool parent_is_waiting = true; 1992 1993 /* 1994 * Check if we can release parent early. 1995 * We either need to have no sed_attrs, or sed_attrs does not 1996 * have POSIX_SPAWN_RETURNERROR or one of the flags, that require 1997 * safe access to the parent proc (passed in sed_parent). 1998 * We then try to get the exec_lock, and only if that works, we can 1999 * release the parent here already. 2000 */ 2001 ppid = spawn_data->sed_parent->p_pid; 2002 if ((!spawn_data->sed_attrs 2003 || (spawn_data->sed_attrs->sa_flags 2004 & (POSIX_SPAWN_RETURNERROR|POSIX_SPAWN_SETPGROUP)) == 0) 2005 && rw_tryenter(&exec_lock, RW_READER)) { 2006 parent_is_waiting = false; 2007 mutex_enter(&spawn_data->sed_mtx_child); 2008 cv_signal(&spawn_data->sed_cv_child_ready); 2009 mutex_exit(&spawn_data->sed_mtx_child); 2010 } 2011 2012 /* don't allow debugger access yet */ 2013 rw_enter(&l->l_proc->p_reflock, RW_WRITER); 2014 have_reflock = true; 2015 2016 error = 0; 2017 /* handle posix_spawn_file_actions */ 2018 if (spawn_data->sed_actions != NULL) { 2019 for (i = 0; i < spawn_data->sed_actions->len; i++) { 2020 fae = &spawn_data->sed_actions->fae[i]; 2021 switch (fae->fae_action) { 2022 case FAE_OPEN: 2023 if (fd_getfile(fae->fae_fildes) != NULL) { 2024 error = fd_close(fae->fae_fildes); 2025 if (error) 2026 break; 2027 } 2028 error = fd_open(fae->fae_path, fae->fae_oflag, 2029 fae->fae_mode, &newfd); 2030 if (error) 2031 break; 2032 if (newfd != fae->fae_fildes) { 2033 error = dodup(l, newfd, 2034 fae->fae_fildes, 0, &retval); 2035 if (fd_getfile(newfd) != NULL) 2036 fd_close(newfd); 2037 } 2038 break; 2039 case FAE_DUP2: 2040 error = dodup(l, fae->fae_fildes, 2041 fae->fae_newfildes, 0, &retval); 2042 break; 2043 case FAE_CLOSE: 2044 if (fd_getfile(fae->fae_fildes) == NULL) { 2045 error = EBADF; 2046 break; 2047 } 2048 error = fd_close(fae->fae_fildes); 2049 break; 2050 } 2051 if (error) 2052 goto report_error; 2053 } 2054 } 2055 2056 /* handle posix_spawnattr */ 2057 if (spawn_data->sed_attrs != NULL) { 2058 int ostat; 2059 struct sigaction sigact; 2060 sigact._sa_u._sa_handler = SIG_DFL; 2061 sigact.sa_flags = 0; 2062 2063 /* 2064 * set state to SSTOP so that this proc can be found by pid. 2065 * see proc_enterprp, do_sched_setparam below 2066 */ 2067 ostat = l->l_proc->p_stat; 2068 l->l_proc->p_stat = SSTOP; 2069 2070 /* Set process group */ 2071 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_SETPGROUP) { 2072 pid_t mypid = l->l_proc->p_pid, 2073 pgrp = spawn_data->sed_attrs->sa_pgroup; 2074 2075 if (pgrp == 0) 2076 pgrp = mypid; 2077 2078 error = proc_enterpgrp(spawn_data->sed_parent, 2079 mypid, pgrp, false); 2080 if (error) 2081 goto report_error; 2082 } 2083 2084 /* Set scheduler policy */ 2085 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_SETSCHEDULER) 2086 error = do_sched_setparam(l->l_proc->p_pid, 0, 2087 spawn_data->sed_attrs->sa_schedpolicy, 2088 &spawn_data->sed_attrs->sa_schedparam); 2089 else if (spawn_data->sed_attrs->sa_flags 2090 & POSIX_SPAWN_SETSCHEDPARAM) { 2091 error = do_sched_setparam(ppid, 0, 2092 SCHED_NONE, &spawn_data->sed_attrs->sa_schedparam); 2093 } 2094 if (error) 2095 goto report_error; 2096 2097 /* Reset user ID's */ 2098 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_RESETIDS) { 2099 error = do_setresuid(l, -1, 2100 kauth_cred_getgid(l->l_cred), -1, 2101 ID_E_EQ_R | ID_E_EQ_S); 2102 if (error) 2103 goto report_error; 2104 error = do_setresuid(l, -1, 2105 kauth_cred_getuid(l->l_cred), -1, 2106 ID_E_EQ_R | ID_E_EQ_S); 2107 if (error) 2108 goto report_error; 2109 } 2110 2111 /* Set signal masks/defaults */ 2112 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_SETSIGMASK) { 2113 mutex_enter(l->l_proc->p_lock); 2114 error = sigprocmask1(l, SIG_SETMASK, 2115 &spawn_data->sed_attrs->sa_sigmask, NULL); 2116 mutex_exit(l->l_proc->p_lock); 2117 if (error) 2118 goto report_error; 2119 } 2120 2121 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_SETSIGDEF) { 2122 /* 2123 * The following sigaction call is using a sigaction 2124 * version 0 trampoline which is in the compatibility 2125 * code only. This is not a problem because for SIG_DFL 2126 * and SIG_IGN, the trampolines are now ignored. If they 2127 * were not, this would be a problem because we are 2128 * holding the exec_lock, and the compat code needs 2129 * to do the same in order to replace the trampoline 2130 * code of the process. 2131 */ 2132 for (i = 1; i <= NSIG; i++) { 2133 if (sigismember( 2134 &spawn_data->sed_attrs->sa_sigdefault, i)) 2135 sigaction1(l, i, &sigact, NULL, NULL, 2136 0); 2137 } 2138 } 2139 l->l_proc->p_stat = ostat; 2140 } 2141 2142 /* now do the real exec */ 2143 error = execve_runproc(l, &spawn_data->sed_exec, parent_is_waiting, 2144 true); 2145 have_reflock = false; 2146 if (error == EJUSTRETURN) 2147 error = 0; 2148 else if (error) 2149 goto report_error; 2150 2151 if (parent_is_waiting) { 2152 mutex_enter(&spawn_data->sed_mtx_child); 2153 cv_signal(&spawn_data->sed_cv_child_ready); 2154 mutex_exit(&spawn_data->sed_mtx_child); 2155 } 2156 2157 /* release our refcount on the data */ 2158 spawn_exec_data_release(spawn_data); 2159 2160 /* and finally: leave to userland for the first time */ 2161 cpu_spawn_return(l); 2162 2163 /* NOTREACHED */ 2164 return; 2165 2166 report_error: 2167 if (have_reflock) { 2168 /* 2169 * We have not passed through execve_runproc(), 2170 * which would have released the p_reflock and also 2171 * taken ownership of the sed_exec part of spawn_data, 2172 * so release/free both here. 2173 */ 2174 rw_exit(&l->l_proc->p_reflock); 2175 execve_free_data(&spawn_data->sed_exec); 2176 } 2177 2178 if (parent_is_waiting) { 2179 /* pass error to parent */ 2180 mutex_enter(&spawn_data->sed_mtx_child); 2181 spawn_data->sed_error = error; 2182 cv_signal(&spawn_data->sed_cv_child_ready); 2183 mutex_exit(&spawn_data->sed_mtx_child); 2184 } else { 2185 rw_exit(&exec_lock); 2186 } 2187 2188 /* release our refcount on the data */ 2189 spawn_exec_data_release(spawn_data); 2190 2191 /* done, exit */ 2192 mutex_enter(l->l_proc->p_lock); 2193 /* 2194 * Posix explicitly asks for an exit code of 127 if we report 2195 * errors from the child process - so, unfortunately, there 2196 * is no way to report a more exact error code. 2197 * A NetBSD specific workaround is POSIX_SPAWN_RETURNERROR as 2198 * flag bit in the attrp argument to posix_spawn(2), see above. 2199 */ 2200 exit1(l, W_EXITCODE(127, 0)); 2201 } 2202 2203 void 2204 posix_spawn_fa_free(struct posix_spawn_file_actions *fa, size_t len) 2205 { 2206 2207 for (size_t i = 0; i < len; i++) { 2208 struct posix_spawn_file_actions_entry *fae = &fa->fae[i]; 2209 if (fae->fae_action != FAE_OPEN) 2210 continue; 2211 kmem_free(fae->fae_path, strlen(fae->fae_path) + 1); 2212 } 2213 if (fa->len > 0) 2214 kmem_free(fa->fae, sizeof(*fa->fae) * fa->len); 2215 kmem_free(fa, sizeof(*fa)); 2216 } 2217 2218 static int 2219 posix_spawn_fa_alloc(struct posix_spawn_file_actions **fap, 2220 const struct posix_spawn_file_actions *ufa, rlim_t lim) 2221 { 2222 struct posix_spawn_file_actions *fa; 2223 struct posix_spawn_file_actions_entry *fae; 2224 char *pbuf = NULL; 2225 int error; 2226 size_t i = 0; 2227 2228 fa = kmem_alloc(sizeof(*fa), KM_SLEEP); 2229 error = copyin(ufa, fa, sizeof(*fa)); 2230 if (error || fa->len == 0) { 2231 kmem_free(fa, sizeof(*fa)); 2232 return error; /* 0 if not an error, and len == 0 */ 2233 } 2234 2235 if (fa->len > lim) { 2236 kmem_free(fa, sizeof(*fa)); 2237 return EINVAL; 2238 } 2239 2240 fa->size = fa->len; 2241 size_t fal = fa->len * sizeof(*fae); 2242 fae = fa->fae; 2243 fa->fae = kmem_alloc(fal, KM_SLEEP); 2244 error = copyin(fae, fa->fae, fal); 2245 if (error) 2246 goto out; 2247 2248 pbuf = PNBUF_GET(); 2249 for (; i < fa->len; i++) { 2250 fae = &fa->fae[i]; 2251 if (fae->fae_action != FAE_OPEN) 2252 continue; 2253 error = copyinstr(fae->fae_path, pbuf, MAXPATHLEN, &fal); 2254 if (error) 2255 goto out; 2256 fae->fae_path = kmem_alloc(fal, KM_SLEEP); 2257 memcpy(fae->fae_path, pbuf, fal); 2258 } 2259 PNBUF_PUT(pbuf); 2260 2261 *fap = fa; 2262 return 0; 2263 out: 2264 if (pbuf) 2265 PNBUF_PUT(pbuf); 2266 posix_spawn_fa_free(fa, i); 2267 return error; 2268 } 2269 2270 int 2271 check_posix_spawn(struct lwp *l1) 2272 { 2273 int error, tnprocs, count; 2274 uid_t uid; 2275 struct proc *p1; 2276 2277 p1 = l1->l_proc; 2278 uid = kauth_cred_getuid(l1->l_cred); 2279 tnprocs = atomic_inc_uint_nv(&nprocs); 2280 2281 /* 2282 * Although process entries are dynamically created, we still keep 2283 * a global limit on the maximum number we will create. 2284 */ 2285 if (__predict_false(tnprocs >= maxproc)) 2286 error = -1; 2287 else 2288 error = kauth_authorize_process(l1->l_cred, 2289 KAUTH_PROCESS_FORK, p1, KAUTH_ARG(tnprocs), NULL, NULL); 2290 2291 if (error) { 2292 atomic_dec_uint(&nprocs); 2293 return EAGAIN; 2294 } 2295 2296 /* 2297 * Enforce limits. 2298 */ 2299 count = chgproccnt(uid, 1); 2300 if (kauth_authorize_process(l1->l_cred, KAUTH_PROCESS_RLIMIT, 2301 p1, KAUTH_ARG(KAUTH_REQ_PROCESS_RLIMIT_BYPASS), 2302 &p1->p_rlimit[RLIMIT_NPROC], KAUTH_ARG(RLIMIT_NPROC)) != 0 && 2303 __predict_false(count > p1->p_rlimit[RLIMIT_NPROC].rlim_cur)) { 2304 (void)chgproccnt(uid, -1); 2305 atomic_dec_uint(&nprocs); 2306 return EAGAIN; 2307 } 2308 2309 return 0; 2310 } 2311 2312 int 2313 do_posix_spawn(struct lwp *l1, pid_t *pid_res, bool *child_ok, const char *path, 2314 struct posix_spawn_file_actions *fa, 2315 struct posix_spawnattr *sa, 2316 char *const *argv, char *const *envp, 2317 execve_fetch_element_t fetch) 2318 { 2319 2320 struct proc *p1, *p2; 2321 struct lwp *l2; 2322 int error; 2323 struct spawn_exec_data *spawn_data; 2324 vaddr_t uaddr; 2325 pid_t pid; 2326 bool have_exec_lock = false; 2327 2328 p1 = l1->l_proc; 2329 2330 /* Allocate and init spawn_data */ 2331 spawn_data = kmem_zalloc(sizeof(*spawn_data), KM_SLEEP); 2332 spawn_data->sed_refcnt = 1; /* only parent so far */ 2333 cv_init(&spawn_data->sed_cv_child_ready, "pspawn"); 2334 mutex_init(&spawn_data->sed_mtx_child, MUTEX_DEFAULT, IPL_NONE); 2335 mutex_enter(&spawn_data->sed_mtx_child); 2336 2337 /* 2338 * Do the first part of the exec now, collect state 2339 * in spawn_data. 2340 */ 2341 error = execve_loadvm(l1, path, argv, 2342 envp, fetch, &spawn_data->sed_exec); 2343 if (error == EJUSTRETURN) 2344 error = 0; 2345 else if (error) 2346 goto error_exit; 2347 2348 have_exec_lock = true; 2349 2350 /* 2351 * Allocate virtual address space for the U-area now, while it 2352 * is still easy to abort the fork operation if we're out of 2353 * kernel virtual address space. 2354 */ 2355 uaddr = uvm_uarea_alloc(); 2356 if (__predict_false(uaddr == 0)) { 2357 error = ENOMEM; 2358 goto error_exit; 2359 } 2360 2361 /* 2362 * Allocate new proc. Borrow proc0 vmspace for it, we will 2363 * replace it with its own before returning to userland 2364 * in the child. 2365 * This is a point of no return, we will have to go through 2366 * the child proc to properly clean it up past this point. 2367 */ 2368 p2 = proc_alloc(); 2369 pid = p2->p_pid; 2370 2371 /* 2372 * Make a proc table entry for the new process. 2373 * Start by zeroing the section of proc that is zero-initialized, 2374 * then copy the section that is copied directly from the parent. 2375 */ 2376 memset(&p2->p_startzero, 0, 2377 (unsigned) ((char *)&p2->p_endzero - (char *)&p2->p_startzero)); 2378 memcpy(&p2->p_startcopy, &p1->p_startcopy, 2379 (unsigned) ((char *)&p2->p_endcopy - (char *)&p2->p_startcopy)); 2380 p2->p_vmspace = proc0.p_vmspace; 2381 2382 TAILQ_INIT(&p2->p_sigpend.sp_info); 2383 2384 LIST_INIT(&p2->p_lwps); 2385 LIST_INIT(&p2->p_sigwaiters); 2386 2387 /* 2388 * Duplicate sub-structures as needed. 2389 * Increase reference counts on shared objects. 2390 * Inherit flags we want to keep. The flags related to SIGCHLD 2391 * handling are important in order to keep a consistent behaviour 2392 * for the child after the fork. If we are a 32-bit process, the 2393 * child will be too. 2394 */ 2395 p2->p_flag = 2396 p1->p_flag & (PK_SUGID | PK_NOCLDWAIT | PK_CLDSIGIGN | PK_32); 2397 p2->p_emul = p1->p_emul; 2398 p2->p_execsw = p1->p_execsw; 2399 2400 mutex_init(&p2->p_stmutex, MUTEX_DEFAULT, IPL_HIGH); 2401 mutex_init(&p2->p_auxlock, MUTEX_DEFAULT, IPL_NONE); 2402 rw_init(&p2->p_reflock); 2403 cv_init(&p2->p_waitcv, "wait"); 2404 cv_init(&p2->p_lwpcv, "lwpwait"); 2405 2406 p2->p_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE); 2407 2408 kauth_proc_fork(p1, p2); 2409 2410 p2->p_raslist = NULL; 2411 p2->p_fd = fd_copy(); 2412 2413 /* XXX racy */ 2414 p2->p_mqueue_cnt = p1->p_mqueue_cnt; 2415 2416 p2->p_cwdi = cwdinit(); 2417 2418 /* 2419 * Note: p_limit (rlimit stuff) is copy-on-write, so normally 2420 * we just need increase pl_refcnt. 2421 */ 2422 if (!p1->p_limit->pl_writeable) { 2423 lim_addref(p1->p_limit); 2424 p2->p_limit = p1->p_limit; 2425 } else { 2426 p2->p_limit = lim_copy(p1->p_limit); 2427 } 2428 2429 p2->p_lflag = 0; 2430 p2->p_sflag = 0; 2431 p2->p_slflag = 0; 2432 p2->p_pptr = p1; 2433 p2->p_ppid = p1->p_pid; 2434 LIST_INIT(&p2->p_children); 2435 2436 p2->p_aio = NULL; 2437 2438 #ifdef KTRACE 2439 /* 2440 * Copy traceflag and tracefile if enabled. 2441 * If not inherited, these were zeroed above. 2442 */ 2443 if (p1->p_traceflag & KTRFAC_INHERIT) { 2444 mutex_enter(&ktrace_lock); 2445 p2->p_traceflag = p1->p_traceflag; 2446 if ((p2->p_tracep = p1->p_tracep) != NULL) 2447 ktradref(p2); 2448 mutex_exit(&ktrace_lock); 2449 } 2450 #endif 2451 2452 /* 2453 * Create signal actions for the child process. 2454 */ 2455 p2->p_sigacts = sigactsinit(p1, 0); 2456 mutex_enter(p1->p_lock); 2457 p2->p_sflag |= 2458 (p1->p_sflag & (PS_STOPFORK | PS_STOPEXEC | PS_NOCLDSTOP)); 2459 sched_proc_fork(p1, p2); 2460 mutex_exit(p1->p_lock); 2461 2462 p2->p_stflag = p1->p_stflag; 2463 2464 /* 2465 * p_stats. 2466 * Copy parts of p_stats, and zero out the rest. 2467 */ 2468 p2->p_stats = pstatscopy(p1->p_stats); 2469 2470 /* copy over machdep flags to the new proc */ 2471 cpu_proc_fork(p1, p2); 2472 2473 /* 2474 * Prepare remaining parts of spawn data 2475 */ 2476 spawn_data->sed_actions = fa; 2477 spawn_data->sed_attrs = sa; 2478 2479 spawn_data->sed_parent = p1; 2480 2481 /* create LWP */ 2482 lwp_create(l1, p2, uaddr, 0, NULL, 0, spawn_return, spawn_data, 2483 &l2, l1->l_class); 2484 l2->l_ctxlink = NULL; /* reset ucontext link */ 2485 2486 /* 2487 * Copy the credential so other references don't see our changes. 2488 * Test to see if this is necessary first, since in the common case 2489 * we won't need a private reference. 2490 */ 2491 if (kauth_cred_geteuid(l2->l_cred) != kauth_cred_getsvuid(l2->l_cred) || 2492 kauth_cred_getegid(l2->l_cred) != kauth_cred_getsvgid(l2->l_cred)) { 2493 l2->l_cred = kauth_cred_copy(l2->l_cred); 2494 kauth_cred_setsvuid(l2->l_cred, kauth_cred_geteuid(l2->l_cred)); 2495 kauth_cred_setsvgid(l2->l_cred, kauth_cred_getegid(l2->l_cred)); 2496 } 2497 2498 /* Update the master credentials. */ 2499 if (l2->l_cred != p2->p_cred) { 2500 kauth_cred_t ocred; 2501 2502 kauth_cred_hold(l2->l_cred); 2503 mutex_enter(p2->p_lock); 2504 ocred = p2->p_cred; 2505 p2->p_cred = l2->l_cred; 2506 mutex_exit(p2->p_lock); 2507 kauth_cred_free(ocred); 2508 } 2509 2510 *child_ok = true; 2511 spawn_data->sed_refcnt = 2; /* child gets it as well */ 2512 #if 0 2513 l2->l_nopreempt = 1; /* start it non-preemptable */ 2514 #endif 2515 2516 /* 2517 * It's now safe for the scheduler and other processes to see the 2518 * child process. 2519 */ 2520 mutex_enter(proc_lock); 2521 2522 if (p1->p_session->s_ttyvp != NULL && p1->p_lflag & PL_CONTROLT) 2523 p2->p_lflag |= PL_CONTROLT; 2524 2525 LIST_INSERT_HEAD(&p1->p_children, p2, p_sibling); 2526 p2->p_exitsig = SIGCHLD; /* signal for parent on exit */ 2527 2528 LIST_INSERT_AFTER(p1, p2, p_pglist); 2529 LIST_INSERT_HEAD(&allproc, p2, p_list); 2530 2531 p2->p_trace_enabled = trace_is_enabled(p2); 2532 #ifdef __HAVE_SYSCALL_INTERN 2533 (*p2->p_emul->e_syscall_intern)(p2); 2534 #endif 2535 2536 /* 2537 * Make child runnable, set start time, and add to run queue except 2538 * if the parent requested the child to start in SSTOP state. 2539 */ 2540 mutex_enter(p2->p_lock); 2541 2542 getmicrotime(&p2->p_stats->p_start); 2543 2544 lwp_lock(l2); 2545 KASSERT(p2->p_nrlwps == 1); 2546 p2->p_nrlwps = 1; 2547 p2->p_stat = SACTIVE; 2548 l2->l_stat = LSRUN; 2549 sched_enqueue(l2, false); 2550 lwp_unlock(l2); 2551 2552 mutex_exit(p2->p_lock); 2553 mutex_exit(proc_lock); 2554 2555 cv_wait(&spawn_data->sed_cv_child_ready, &spawn_data->sed_mtx_child); 2556 error = spawn_data->sed_error; 2557 mutex_exit(&spawn_data->sed_mtx_child); 2558 spawn_exec_data_release(spawn_data); 2559 2560 rw_exit(&p1->p_reflock); 2561 rw_exit(&exec_lock); 2562 have_exec_lock = false; 2563 2564 *pid_res = pid; 2565 return error; 2566 2567 error_exit: 2568 if (have_exec_lock) { 2569 execve_free_data(&spawn_data->sed_exec); 2570 rw_exit(&p1->p_reflock); 2571 rw_exit(&exec_lock); 2572 } 2573 mutex_exit(&spawn_data->sed_mtx_child); 2574 spawn_exec_data_release(spawn_data); 2575 2576 return error; 2577 } 2578 2579 int 2580 sys_posix_spawn(struct lwp *l1, const struct sys_posix_spawn_args *uap, 2581 register_t *retval) 2582 { 2583 /* { 2584 syscallarg(pid_t *) pid; 2585 syscallarg(const char *) path; 2586 syscallarg(const struct posix_spawn_file_actions *) file_actions; 2587 syscallarg(const struct posix_spawnattr *) attrp; 2588 syscallarg(char *const *) argv; 2589 syscallarg(char *const *) envp; 2590 } */ 2591 2592 int error; 2593 struct posix_spawn_file_actions *fa = NULL; 2594 struct posix_spawnattr *sa = NULL; 2595 pid_t pid; 2596 bool child_ok = false; 2597 rlim_t max_fileactions; 2598 proc_t *p = l1->l_proc; 2599 2600 error = check_posix_spawn(l1); 2601 if (error) { 2602 *retval = error; 2603 return 0; 2604 } 2605 2606 /* copy in file_actions struct */ 2607 if (SCARG(uap, file_actions) != NULL) { 2608 max_fileactions = 2 * min(p->p_rlimit[RLIMIT_NOFILE].rlim_cur, 2609 maxfiles); 2610 error = posix_spawn_fa_alloc(&fa, SCARG(uap, file_actions), 2611 max_fileactions); 2612 if (error) 2613 goto error_exit; 2614 } 2615 2616 /* copyin posix_spawnattr struct */ 2617 if (SCARG(uap, attrp) != NULL) { 2618 sa = kmem_alloc(sizeof(*sa), KM_SLEEP); 2619 error = copyin(SCARG(uap, attrp), sa, sizeof(*sa)); 2620 if (error) 2621 goto error_exit; 2622 } 2623 2624 /* 2625 * Do the spawn 2626 */ 2627 error = do_posix_spawn(l1, &pid, &child_ok, SCARG(uap, path), fa, sa, 2628 SCARG(uap, argv), SCARG(uap, envp), execve_fetch_element); 2629 if (error) 2630 goto error_exit; 2631 2632 if (error == 0 && SCARG(uap, pid) != NULL) 2633 error = copyout(&pid, SCARG(uap, pid), sizeof(pid)); 2634 2635 *retval = error; 2636 return 0; 2637 2638 error_exit: 2639 if (!child_ok) { 2640 (void)chgproccnt(kauth_cred_getuid(l1->l_cred), -1); 2641 atomic_dec_uint(&nprocs); 2642 2643 if (sa) 2644 kmem_free(sa, sizeof(*sa)); 2645 if (fa) 2646 posix_spawn_fa_free(fa, fa->len); 2647 } 2648 2649 *retval = error; 2650 return 0; 2651 } 2652 2653 void 2654 exec_free_emul_arg(struct exec_package *epp) 2655 { 2656 if (epp->ep_emul_arg_free != NULL) { 2657 KASSERT(epp->ep_emul_arg != NULL); 2658 (*epp->ep_emul_arg_free)(epp->ep_emul_arg); 2659 epp->ep_emul_arg_free = NULL; 2660 epp->ep_emul_arg = NULL; 2661 } else { 2662 KASSERT(epp->ep_emul_arg == NULL); 2663 } 2664 } 2665 2666 #ifdef DEBUG_EXEC 2667 static void 2668 dump_vmcmds(const struct exec_package * const epp, size_t x, int error) 2669 { 2670 struct exec_vmcmd *vp = &epp->ep_vmcmds.evs_cmds[0]; 2671 size_t j; 2672 2673 if (error == 0) 2674 DPRINTF(("vmcmds %u\n", epp->ep_vmcmds.evs_used)); 2675 else 2676 DPRINTF(("vmcmds %zu/%u, error %d\n", x, 2677 epp->ep_vmcmds.evs_used, error)); 2678 2679 for (j = 0; j < epp->ep_vmcmds.evs_used; j++) { 2680 DPRINTF(("vmcmd[%zu] = vmcmd_map_%s %#" 2681 PRIxVADDR"/%#"PRIxVSIZE" fd@%#" 2682 PRIxVSIZE" prot=0%o flags=%d\n", j, 2683 vp[j].ev_proc == vmcmd_map_pagedvn ? 2684 "pagedvn" : 2685 vp[j].ev_proc == vmcmd_map_readvn ? 2686 "readvn" : 2687 vp[j].ev_proc == vmcmd_map_zero ? 2688 "zero" : "*unknown*", 2689 vp[j].ev_addr, vp[j].ev_len, 2690 vp[j].ev_offset, vp[j].ev_prot, 2691 vp[j].ev_flags)); 2692 if (error != 0 && j == x) 2693 DPRINTF((" ^--- failed\n")); 2694 } 2695 } 2696 #endif 2697